World's 15 most valuable companies

BHP Billiton is the world's largest mining company and the largest company in Australia by market capitalisation.

It was created in 2001 by the merger of Australia's Broken Hill Proprietary Company (BHP) and the Anglo-Dutch Billiton. BHP Billiton is listed on the London Stock Exchange and is a constituent of the FTSE 100 Index.

World's 15 most valuable companies

Petrobras is the largest company in Latin America by market capitalisation and revenue. Petrobras controls significant oil and energy assets in 18 countries in Africa, North America, South America, Europe and Asia.

World's 15 most valuable companies

A global oil and gas company headquartered in The Hague, the Netherlands, it is the largest energy company and the second-largest company in the world in terms of revenues. It is one of the six oil and gas 'supermajors'.

World's 15 most valuable companies

The General Electric Company is ranked as the world's second largest company by Forbes. From aircraft engines and power generation to financial services, medical imaging, and television programming, GE operates in more than 100 countries.

World's 15 most valuable companies

Wal-Mart Stores, Inc runs a chain of large discount department stores and a chain of warehouse stores. In 2010, it was the world's largest public corporation by revenue, according to the Forbes Global 2000 list. The company was founded by Sam Walton in 1962 has 8,500 stores in 15 countries.

World's 15 most valuable companies

Beginning in 1996, Stanford University graduate students Larry Page and Sergey Brin built a search engine called 'BackRub' that used links to determine the importance of individual web pages. By 1998, this took the form of Google, one of the most valuable technology brands.

World's 15 most valuable companies

Chevron Corporation, an American multinational energy corporation is active in more than 180 countries. Chevron is one of the world's six 'supermajor' oil companies. For the past five years, Chevron has been continuously ranked as the one of America's 5 largest corporations by Fortune.

World's 15 most valuable companies

The company's revenue in 2010 stands at $78.9 billion. Around 23 of P&G's brands have more than a billion dollars in net annual sales, and 18 other products have sales between $500 million and $1 billion.

World's 15 most valuable companies

International Business Machines, founded in 1911, manufactures and sells computer hardware and software. It offers infrastructure, hosting and consulting services in areas ranging from mainframe computers to nanotechnology. In 2010, Fortune ranked IBM as the 20th largest firm in the United States.